Pnuematic Gearshift

[ben]

Hello all,

Much against my better judgement I've agreed to design and manufacture (in addition to the suspension) a pnuematic gearshift for our new FSAE car (UBRacing - www.fsae.bham.ac.uk) (http://www.fsae.bham.ac.uk)).
We've pretty much decided on a manual clutch via a cable, and twin single-acting actuators for the shift. We will have a total loss system with a bottle and regulator with solenoid acutated valves.

The only area I'm currently having problems with is the shift to nuetral. It's obviously a half shift between 1st and 2nd (Honda CBR600Fx) and I would like to know if any of you guys have any advice you could give me on how to get the thing in neutral.

Do you do it manually or have a seperate neutral button that operates the actuators over a different stroke?

All ideas welcome.

Cheers.

Ben

[ben]

Hello all,

Much against my better judgement I've agreed to design and manufacture (in addition to the suspension) a pnuematic gearshift for our new FSAE car (UBRacing - www.fsae.bham.ac.uk) (http://www.fsae.bham.ac.uk)).
We've pretty much decided on a manual clutch via a cable, and twin single-acting actuators for the shift. We will have a total loss system with a bottle and regulator with solenoid acutated valves.

The only area I'm currently having problems with is the shift to nuetral. It's obviously a half shift between 1st and 2nd (Honda CBR600Fx) and I would like to know if any of you guys have any advice you could give me on how to get the thing in neutral.

Do you do it manually or have a seperate neutral button that operates the actuators over a different stroke?

All ideas welcome.

Cheers.

Ben

[Charlie]

Just bump the button lightly for lazy cylinder action and it should drop into nuetral. The biggest problem we've had is going to nuetral when you'd rather not (on the track).

-Charlie Ping
Auburn University FSAE 1999-present

[Erik C]

I have heard of some teams modifying the shifting pattern so that instead of 1-N-2-3.... it's N-1-2-3.... You can also try removing the detent spring for easier actuation, but you have to make sure that the actuator can go back to its "neutral" position. I am not sure if this will work or not, as I have never removed the spring from my motorcycle. BTW, if you guys are running a dry sump, it's fairy simple to add an additional pressure pump, then it's merely a matter of designing an accumulator, and then getting the actuation to work.....easy /infopop/emoticons/icon_wink.gif

[Angry Joe]

We did it the ghetto way: Put it into neutral by manually pushing the shifter lever at the engine. We too had a problem with false neutrals, although the R6 tranny is supposed to skip neutral when in motion

Lehigh Formula SAE

www.lehigh.edu/~insae/formula (http://www.lehigh.edu/~insae/formula)

[Travis R]

We used a kliktronic with our f4i in 2002. I like it, but finding neutral was a little tricky at first. It's become a lot easier as the tranny got broken in (sloppy) and we got better with the buttons.
The other problem is grabbing neutral on your way to second. But if you hold the button down just a hair longer it isn't a problem. Our ECU will do ignition cut for shifting, but I like it better turned off. But that's just me.

Travis Rouse - Test Pilot - The University of Texas (Austin)
http://www.ls1power.net/RX7/autox4_slide.jpg

[BStoney]

We are running an F4i this year at UC. We also were concerned with the 1/2 shift between 1st and Neutral and then Neutral and 2nd. Modifying the gears and the shift barrel might be the way to go??..but can't let the cat outta the bag yet. Peace.

B.J. Stoney
University of Cincinnati
bjstoney13@yahoo.com

[Bam Bam]

Here's a hint, Drop 1st (rip it out) and gear your car to use 2nd to 6th. I'm guessing you don't get a whole lotta use out of 5th and 6th if your using 1st for anything but massive burn outs.
Now 1st gear becomes neutral.

Problem solved.

[BStoney]

Correct. Rip out first, and put neutral there. A little modification to the shift barrel and you can even tell when you're in neutral and it becomes the much desired whole shift from neutral to 1st.

B.J. Stoney
University of Cincinnati
bjstoney13@yahoo.com

[Duke of URL]

Has anyone considered using a servo for shifting?
Then you could duplicate the original shifting motions from the original motorcycle.
No fuss, no worries.